HELP 8520 update to OS 5

I have a blackberry 8520 on T-Mobile running 4.6 wanting to update to OS 5

What I did so far is:
1. downloaded 5.0.0.860 officially released byWind Hellas
2. Download the OS file to the PC then install it to the PC by running (double clicking) the file you downloaded.
3. Go to c:\program files\common files\research in motion\apploader and delete the file named "vendor.xml."
4. Plug in BB and double click on "Loader.exe." It's located in the same place as the above vendor.xml file.

After I did all that I went into BB download manager 5 to do an update and got this message

Only active BlackBerry service subscribers are entitled to install the BB device software upgrade*

HELP I AM NEW TO THE BB WORLD I AM COMING FROM THE IPHONE WORLD SO I DO KNOW ABOUT MODDING.